The springs from Wilson Combat (whoever makes them) are a different style of spring than the factory extension springs. They're a beehive-style spring with wider central coils and a longer coil pitch. It's a fairly space-efficient spring that works best with tailed followers. The factory extension springs are narrower, with more closely-spaced coils. They're designed to fit into cup-style followers and pass through the follower stop in the factory extension tubes with minimal resistance. I also think the Wilson springs are chrome-silicon, while the Remington springs are 17-7 stainless, but don't quote me on that.
I've used both, and I think they're both good springs. The Remington spring will probably give you more force, since it's a shared part that's also used in the factory +3 extensions, but either should be stiff enough to run reliably. I do think the Wilson spring is better used in straight tubes, as it's a bit wide for the follower stop in the factory extensions, and you might notice a bit of drag if you listen or feel carefully, but I know other folks have used them in the factory +2 extension without any functional issues.
I do prefer to snap the center post off the Wilson follower (assuming Wilson hasn't changed the follower in the last few years). I've seen those posts crack open shell rims, which can make a mess if you're using buffered ammo. I think the resultant hole is easier to pick up by touch, anyway.
